Problem: What is the next term of the geometric sequence? $\dfrac{81}{25},\dfrac{27}{5},9,$
Answer: In a geometric sequence there's a constant ratio between subsequent terms. Let's find that ratio, and use it to find which term should come after the last one that is given, which is $9$. Each term is ${\dfrac53}$ times the term before it. ${\times \dfrac53\,\curvearrowright}$ ${\times \dfrac53\,\curvearrowright}$ $\dfrac{81}{25},$ $\dfrac{27}{5},$ $9$ So the next term is $9\cdot{\dfrac53}=15$. The missing term is $15$.